Field of the Invention
The present invention relates to a circuit substrate and a package structure, and in particular to a circuit substrate and a package structure with a high routing density.
Description of the Related Art
In semiconductor package assembly technology, chip carriers are currently used to connect semiconductor integrated circuit (IC) chips to electronic devices in the lower layered-level, such as circuit boards like motherboards or module boards. The circuit boards are usually used as high pin-count chip carriers. The circuit boards are formed by alternatively laminating a plurality of patterned conductive layers and a plurality of dielectric layers. Any two of the patterned conductive layers can be electrically connected to each other through conductive vias.
However, the routing density and the bump density of the circuit boards must be increased to meet the requirements of the integrated multi-chip packages and the multiple input/output (I/O) terminals chips.
Thus, a novel circuit substrate and a novel package structure are desirable.